This invention relates to high frequency transformer and rectifier circuits, particularly transformer and rectifier circuits for switched mode power supplies and the like. The module may be used in a matrix transformer array as any other matrix transformer module, except that it will have a secondary turns of one-half turn. For more information about matrix transformers, please refer to U.S. Pat. Nos. 4,665,357; 4,845,606; 4,942,353; 4,978,906; 5,093,646; and 5,479,146, the specifications and drawings of which are incorporated herein by reference.
"High frequency" may be hundreds of kilohertz, or even megahertz, but in very large transformers "high frequency" design techniques are advantageous even at commercial line frequency. Whenever parasitic reactive impedances are important, or the conductor dimensions are greater than the penetration depth, the teachings of this invention are applicable.
In high frequency power transformers, it is particularly important to reduce leakage inductance. This invention teaches several features which cooperate to accomplish that objective. First, the arrangement of the winding terminations are such that much of the leakage inductance in the external circuits proximate to the transformer is canceled. Second, the external circuits proximate to the transformer are arranged for low leakage inductance. Third, by using a half-turn arrangement, the number of primary turns needed is reduced by half. Since the primary leakage inductance is proportional to the square of the turns in the primary, the primary leakage inductance is reduced.
Additional benefits are that the design is inherently low profile, the thermal paths are very short and spread out, the component parts are inexpensive and very rugged.